Heart valve service provision in the United Kingdom and the effect of the COVID 19 pandemic; improved but must do better. A British Heart Valve Society national survey

BACKGROUND

Outpatient care for patients with heart valve disease (HVD) is best provided by valve clinics delivered by specialists. Modern day practice in the United Kingdom (UK) is currently poorly understood and has not been evaluated for nearly a decade. Furthermore, the COVID 19 pandemic changed the management of many chronic diseases, and how this has impacted patients with heart valve disease is unclear.

METHODS

A British Heart Valve Society survey was sent to 161 hospitals throughout the UK.

RESULTS

There was a general valve clinic in 46 of the 68 hospitals (68%), in 19 of 23 Heart Centres (83%) and 29 of 45 DGHs (64%). Across all settings, 3824 new patients and 17,980 follow up patients were seen in valve clinics per annum. The mean number of patients per hospital were 197 (median 150, range 48-550) for new patients and 532 (median 400, range 150-2000) for follow up. On the day echocardiography was available in 55% of valve clinics. In patients with severe HVD, serum brain natriuretic peptide (BNP) was measured routinely in 39% of clinics and exercise testing routinely performed in 49% of clinics. A patient helpline was available in 27% of clinics. 78% of centres with a valve clinic had a valve multidisciplinary team meeting (MDT). 45% centres had an MDT co-ordinator and MDT outcomes were recorded on a database in 64%. COVID-19 had a major impact on valve services in 54 (95%) hospitals.

CONCLUSIONS

There has been an increase in the number of valve clinics since 2015 from 21 to 68% but the penetration is still well short of the expected 100%, meaning that valve clinics only serve a small proportion of patients requiring surveillance for HVD. COVID-19 had a major impact on the care of patients with HVD in the majority of UK centres surveyed.

Epigenetic alterations fuel brain metastasis via regulating inflammatory cascade

Brain metastasis (BrM) is a major threat to the survival of melanoma, breast, and lung cancer patients. Circulating tumor cells (CTCs) cross the blood-brain barrier (BBB) and sustain in the brain microenvironment. Genetic mutations and epigenetic modifications have been found to be critical in controlling key aspects of cancer metastasis. Metastasizing cells confront inflammation and gradually adapt in the unique brain microenvironment. Currently, it is one of the major areas that has gained momentum. Researchers are interested in the factors that modulate neuroinflammation during BrM. We review here various epigenetic factors and mechanisms modulating neuroinflammation and how this helps CTCs to adapt and survive in the brain microenvironment. Since epigenetic changes could be modulated by targeting enzymes such as histone/DNA methyltransferase, deacetylases, acetyltransferases, and demethylases, we also summarize our current understanding of potential drugs targeting various aspects of epigenetic regulation in BrM.

Chemotherapy in pediatric brain tumor and the challenge of the blood-brain barrier

BACKGROUND

Pediatric brain tumors (PBT) stand as the leading cause of cancer-related deaths in children. Chemoradiation protocols have improved survival rates, even for non-resectable tumors. Nonetheless, radiation therapy carries the risk of numerous adverse effects that can have long-lasting, detrimental effects on the quality of life for survivors. The pursuit of chemotherapeutics that could obviate the need for radiotherapy remains ongoing. Several anti-tumor agents, including sunitinib, valproic acid, carboplatin, and panobinostat, have shown effectiveness in various malignancies but have not proven effective in treating PBT. The presence of the blood-brain barrier (BBB) plays a pivotal role in maintaining suboptimal concentrations of anti-cancer drugs in the central nervous system (CNS). Ongoing research aims to modulate the integrity of the BBB to attain clinically effective drug concentrations in the CNS. However, current findings on the interaction of exogenous chemical agents with the BBB remain limited and do not provide a comprehensive explanation for the ineffectiveness of established anti-cancer drugs in PBT.

METHODS

We conducted our search for chemotherapeutic agents associated with the blood-brain barrier (BBB) using the following keywords: Chemotherapy in Cancer, Chemotherapy in Brain Cancer, Chemotherapy in PBT, BBB Inhibition of Drugs into CNS, Suboptimal Concentration of CNS Drugs, PBT Drugs and BBB, and Potential PBT Drugs. We reviewed each relevant article before compiling the information in our manuscript. For the generation of figures, we utilized BioRender software.

FOCUS

We focused our article search on chemical agents for PBT and subsequently investigated the role of the BBB in this context. Our search criteria included clinical trials, both randomized and non-randomized studies, preclinical research, review articles, and research papers.

FINDING

Our research suggests that, despite the availability of potent chemotherapeutic agents for several types of cancer, the effectiveness of these chemical agents in treating PBT has not been comprehensively explored. Additionally, there is a scarcity of studies examining the role of the BBB in the suboptimal outcomes of PBT treatment, despite the effectiveness of these drugs for other types of tumors.

Synthesis and Antitumor Activity of Brominated-Ormeloxifene (Br-ORM) against Cervical Cancer

Aberrant regulation of β-catenin signaling is strongly linked with cancer proliferation, invasion, migration, and metastasis, thus, small molecules that can inhibit this pathway might have great clinical significance. Our molecular modeling studies suggest that ormeloxifene (ORM), a triphenylethylene molecule that docks with β-catenin, and its brominated analogue (Br-ORM) bind more effectively with relatively less energy (-7.6 kcal/mol) to the active site of β-catenin as compared to parent ORM. Herein, we report the synthesis and characterization of a Br-ORM by NMR and FTIR, as well as its anticancer activity in cervical cancer models. Br-ORM treatment effectively inhibited tumorigenic features (cell proliferation and colony-forming ability, etc.) and induced apoptotic death, as evident by pronounced PARP cleavage. Furthermore, Br-ORM treatment caused cell cycle arrest at the G1-S phase. Mechanistic investigation revealed that Br-ORM targets the key proteins involved in promoting epithelial-mesenchymal transition (EMT), as demonstrated by upregulation of E-cadherin and repression of N-cadherin, Vimentin, Snail, MMP-2, and MMP-9 expression. Br-ORM also represses the expression and nuclear subcellular localization of β-catenin. Consequently, Br-ORM treatment effectively inhibited tumor growth in an orthotopic cervical cancer xenograft mouse model along with EMT associated changes as compared to vehicle control-treated mice. Altogether, experimental findings suggest that Br-ORM is a novel, promising β-catenin inhibitor and therefore can be harnessed as a potent anticancer small molecule for cervical cancer treatment.

Thermodynamic Insights into Variation in Thermomechanical and Physical Properties of Isotactic Polypropylene: Effect of Shear and Cooling Rates

In order to elucidate the effect of shear and cooling process on structural, thermomechanical, and physical properties of polymer melt, excess entropy, a thermodynamic quantity is calculated from radial distribution function generated from equilibrated parts of the molecular simulation trajectories. The structural properties are calculated, which includes the density of polypropylene melt, end to end distance, radius of gyration of the polypropylene polymer chain, and monomer-monomer radial distribution function. Non-equilibrium molecular dynamics simulation was employed to investigate the role of the applied shear rate on the properties of polypropylene. Furthermore, a range of cooling rates were employed to cool the melt. Thermomechanical properties, such as Young's modulus, and physical properties, such as glass transition temperature, were determined for different cases. Results showed that slow cooling and high shear substantially improved the Young's modulus and glass transition temperature of the i-PP. Furthermore, a two-body contribution to the excess entropy was used to elucidate the structure-property relationships in the polymer melt as well as the glassy state and the dependence of shear and cooling rate on these properties. We have used the Rosenfeld excess entropy-viscosity relationship to calculate the viscous behavior of the polymer under a steady shear condition.

Immunotherapy: an emerging modality to checkmate brain metastasis

The diagnosis of brain metastasis (BrM) has historically been a dooming diagnosis that is nothing less than a death sentence, with few treatment options for palliation or prolonging life. Among the few treatment options available, brain radiotherapy (RT) and surgical resection have been the backbone of therapy. Within the past couple of years, immunotherapy (IT), alone and in combination with traditional treatments, has emerged as a reckoning force to combat the spread of BrM and shrink tumor burden. This review compiles recent reports describing the potential role of IT in the treatment of BrM in various cancers. It also examines the impact of the tumor microenvironment of BrM on regulating the spread of cancer and the role IT can play in mitigating that spread. Lastly, this review also focuses on the future of IT and new clinical trials pushing the boundaries of IT in BrM.

A review on computational studies and bioinformatics analysis of potential drugs against monkeypox virus

Monkeypox, a viral disease that is caused by monkeypox virus and occurs mainly in central and western Africa. However, recently it is spreading worldwide and took the focus of the scientific world towards it. Therefore, we made an attempt to cluster all the related information that may make it easy for the researchers to get the information easily and carry out their research smoothly to find prophylaxis against this emerging virus. There are very few researches found available on monkeypox. Almost all the studies were focused on smallpox virus and the recommended vaccines and therapeutics for monkeypox virus were originally developed for smallpox virus. Though these are recommended for emergency cases, they are not fully effective and specific against monkeypox. For this, here we also took the help of bioinformatics tools to screen potential drug candidates against this growing burden. Some potential antiviral plant metabolites, inhibitors and available drugs were scrutinized that can block the essential survival proteins of this virus. All the compounds Amentoflavone, Pseudohypericin, Adefovirdipiboxil, Fialuridin, Novobiocin and Ofloxacin showed elite binding efficiency with suitable ADME properties and Amentoflavone and Pseudohypericin showed stability in MD simulation study indicating their potency as probable drugs against this emerging virus.Communicated by Ramaswamy H. Sarma.

Abstract 3760: MicroRNA-1 run down the growth and metastasis of small cell lung cancer

Small cell lung cancer (SCLC) is a highly aggressive and metastatic lung cancer subtype with universal relapse and poor prognosis. The lack of potential drug targets limits targeted therapies for SCLC patients. To track down the potential therapeutic molecules in SCLC, we performed micro-RNA sequencing from the serum samples of SCLC patients and compared with the bulk RNA-sequencing data from SCLC tumor tissues. A consistent downregulation of microRNA-1 (miR-1) was observed in the SCLC patient serum samples, cell lines, and tumor tissues compared to their matched normal control. Overexpression of miR-1 in SCLC cell lines decreased cell growth and oncogenic signaling. Metastatic studies using the intracardiac injection model of SCLC cell lines showed that miR-1 overexpression decreases distant organ metastasis. Interestingly, the loss of function studies using miR-1Zip/sponging showed increased tumorigenesis and metastasis in SCLC subcutaneous and intracardiac xenografts. Mechanistic investigations revealed the CXCR4/FOXM1/RRM2 axis as a unique downstream target of miR-1 in SCLC. We found that FOXM1 transcriptionally regulates the RRM2 expression by directly binding to its promoter site, and miR-1 modulates these interactions through CXCR4. The results of the present study provided a strong preclinical rationale that miR-1 has a high potential for developing innovative SCLC therapies.

Citation Format: Parvez Khan, Jawed A. Siddiqui, Shailendra Kumar Maurya, Tamara Mirzapoiazova, Prakash G. Kshirsagar, Ramakanth Chirravuri Venkata, Sanjib Chaudhary, Ranjana Kanchan, Naveenkumar Perumal, Mahek Fatima, Md Arafat Khan, Asad Ur Rehman, Imayavaramban Lakshmanan, Sidharth Mahapatra, Prakash Kulkarni, Apar Kishor Ganti, Maneesh Jain, Ravi Salgia, Surinder Kumar Batra, Mohd Wasim Nasser. MicroRNA-1 run down the growth and metastasis of small cell lung cancer. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3760.

FOXM1: A small fox that makes more tracks for cancer progression and metastasis

Transcription factors (TFs) are indispensable for the modulation of various signaling pathways associated with normal cell homeostasis and disease conditions. Among cancer-related TFs, FOXM1 is a critical molecule that regulates multiple aspects of cancer cells, including growth, metastasis, recurrence, and stem cell features. FOXM1 also impacts the outcomes of targeted therapies, chemotherapies, and immune checkpoint inhibitors (ICIs) in various cancer types. Recent advances in cancer research strengthen the cancer-specific role of FOXM1, providing a rationale to target FOXM1 for developing targeted therapies. This review compiles the recent studies describing the pivotal role of FOXM1 in promoting metastasis of various cancer types. It also implicates the contribution of FOXM1 in the modulation of chemotherapeutic resistance, antitumor immune response/immunotherapies, and the potential of small molecule inhibitors of FOXM1.

Mucins as Potential Biomarkers for Early Detection of Cancer

Early detection significantly correlates with improved survival in cancer patients. So far, a limited number of biomarkers have been validated to diagnose cancers at an early stage. Considering the leading cancer types that contribute to more than 50% of deaths in the USA, we discuss the ongoing endeavors toward early detection of lung, breast, ovarian, colon, prostate, liver, and pancreatic cancers to highlight the significance of mucin glycoproteins in cancer diagnosis. As mucin deregulation is one of the earliest events in most epithelial malignancies following oncogenic transformation, these high-molecular-weight glycoproteins are considered potential candidates for biomarker development. The diagnostic potential of mucins is mainly attributed to their deregulated expression, altered glycosylation, splicing, and ability to induce autoantibodies. Secretory and shed mucins are commonly detected in patients' sera, body fluids, and tumor biopsies. For instance, CA125, also called MUC16, is one of the biomarkers implemented for the diagnosis of ovarian cancer and is currently being investigated for other malignancies. Similarly, MUC5AC, a secretory mucin, is a potential biomarker for pancreatic cancer. Moreover, anti-mucin autoantibodies and mucin-packaged exosomes have opened new avenues of biomarker development for early cancer diagnosis. In this review, we discuss the diagnostic potential of mucins in epithelial cancers and provide evidence and a rationale for developing a mucin-based biomarker panel for early cancer detection.

MicroRNA-1 attenuates the growth and metastasis of small cell lung cancer through CXCR4/FOXM1/RRM2 axis

BACKGROUND

Small cell lung cancer (SCLC) is an aggressive lung cancer subtype that is associated with high recurrence and poor prognosis. Due to lack of potential drug targets, SCLC patients have few therapeutic options. MicroRNAs (miRNAs) provide an interesting repertoire of therapeutic molecules; however, the identification of miRNAs regulating SCLC growth and metastasis and their precise regulatory mechanisms are not well understood.

METHODS

To identify novel miRNAs regulating SCLC, we performed miRNA-sequencing from donor/patient serum samples and analyzed the bulk RNA-sequencing data from the tumors of SCLC patients. Further, we developed a nanotechnology-based, highly sensitive method to detect microRNA-1 (miR-1, identified miRNA) in patient serum samples and SCLC cell lines. To assess the therapeutic potential of miR-1, we developed various in vitro models, including miR-1 sponge (miR-1Zip) and DOX-On-miR-1 (Tet-ON) inducible stable overexpression systems. Mouse models derived from intracardiac injection of SCLC cells (miR-1Zip and DOX-On-miR-1) were established to delineate the role of miR-1 in SCLC metastasis. In situ hybridization and immunohistochemistry were used to analyze the expression of miR-1 and target proteins (mouse and human tumor specimens), respectively. Dual-luciferase assay was used to validate the target of miR-1, and chromatin immunoprecipitation assay was used to investigate the protein-gene interactions.

RESULTS

A consistent downregulation of miR-1 was observed in tumor tissues and serum samples of SCLC patients compared to their matched normal controls, and these results were recapitulated in SCLC cell lines. Gain of function studies of miR-1 in SCLC cell lines showed decreased cell growth and oncogenic signaling, whereas loss of function studies of miR-1 rescued this effect. Intracardiac injection of gain of function of miR-1 SCLC cell lines in the mouse models showed a decrease in distant organ metastasis, whereas loss of function of miR-1 potentiated growth and metastasis. Mechanistic studies revealed that CXCR4 is a direct target of miR-1 in SCLC. Using unbiased transcriptomic analysis, we identified CXCR4/FOXM1/RRM2 as a unique axis that regulates SCLC growth and metastasis. Our results further showed that FOXM1 directly binds to the RRM2 promoter and regulates its activity in SCLC.

CONCLUSIONS

Our findings revealed that miR-1 is a critical regulator for decreasing SCLC growth and metastasis. It targets the CXCR4/FOXM1/RRM2 axis and has a high potential for the development of novel SCLC therapies. MicroRNA-1 (miR-1) downregulation in the tumor tissues and serum samples of SCLC patients is an important hallmark of tumor growth and metastasis. The introduction of miR-1 in SCLC cell lines decreases cell growth and metastasis. Mechanistically, miR-1 directly targets CXCR4, which further prevents FOXM1 binding to the RRM2 promoter and decreases SCLC growth and metastasis.

Concordance of three approaches for operationalizing outcome definitions for multidrug-resistant TB

BACKGROUND: The WHO provides standardized outcome definitions for rifampicin-resistant (RR) and multidrug-resistant (MDR) TB. However, operationalizing these definitions can be challenging in some clinical settings, and incorrect classification may generate bias in reporting and research. Outcomes calculated by algorithms can increase standardization and be adapted to suit the research question. We evaluated concordance between clinician-assigned treatment outcomes and outcomes calculated based on one of two standardized algorithms, one which identified failure at its earliest possible recurrence (i.e., failure-dominant algorithm), and one which calculated the outcome based on culture results at the end of treatment, regardless of early occurrence of failure (i.e., success-dominant algorithm).METHODS: Among 2,525 patients enrolled in the multi-country endTB observational study, we calculated the frequencies of concordance using cross-tabulations of clinician-assigned and algorithm-assigned outcomes. We summarized the common discrepancies.RESULTS: Treatment success calculated by algorithms had high concordance with treatment success assigned by clinicians (95.8 and 97.7% for failure-dominant and success-dominant algorithms, respectively). The frequency and pattern of the most common discrepancies varied by country.CONCLUSION: High concordance was found between clinician-assigned and algorithm-assigned outcomes. Heterogeneity in discrepancies across settings suggests that using algorithms to calculate outcomes may minimize bias.

Approaches and Perspective of Coarse-Grained Modeling and Simulation for Polymer-Nanoparticle Hybrid Systems

Molecular modeling and simulations have emerged as effective and indispensable tools to characterize polymeric systems. They provide fundamental and essential insights to design a product of the required properties and to improve the understanding of a phenomenon at the molecular level for a particular system. The polymer-nanoparticle hybrids are materials with outstanding properties and correspondingly large applications whose study has benefited from this new paradigm. However, despite the significant expansion of modern day computational powers, investigation of the long time and large length scale phenomenon in polymeric and polymer-nanoparticle systems is still a challenging task to complete through all-atom molecular dynamics (AA-MD) simulations. To circumvent this problem, a variety of coarse-grained (CG) models have been proposed, ranging from the generic CG models for qualitative properties predictions to more realistic chemically specific CG models for quantitative properties predictions. These CG models have already delivered some success stories in the study of several spatial and temporal evolutions of many processes. Some of these studies were beyond the feasibility of traditional atomistic resolution models due to either the size or the time constraints. This review captures the different types of popular CG approaches that are utilized in the investigation of the microscopic behavior of polymer-nanoparticle hybrid systems. The rationale of this article is to furnish an overview of the popular CG approaches and their applications, to review several important and most recent developments, and to delineate the perspectives on future directions in the field.

Emerging role of chemokines in small cell lung cancer: Road signs for metastasis, heterogeneity, and immune response

Small cell lung cancer (SCLC) is a recalcitrant, relatively immune-cold, and deadly subtype of lung cancer. SCLC has been viewed as a single or homogenous disease that includes deletion or inactivation of the two major tumor suppressor genes (TP53 and RB1) as a key hallmark. However, recent sightings suggest the complexity of SCLC tumors that comprises highly dynamic multiple subtypes contributing to high intratumor heterogeneity. Furthermore, the absence of targeted therapies, the understudied tumor immune microenvironment (TIME), and subtype plasticity are also responsible for therapy resistance. Secretory chemokines play a crucial role in immunomodulation by trafficking immune cells to the tumors. Chemokines and cytokines modulate the anti-tumor immune response and wield a pro-/anti-tumorigenic effect on SCLC cells after binding to cognate receptors. In this review, we summarize and highlight recent findings that establish the role of chemokines in SCLC growth and metastasis, and sophisticated intratumor heterogeneity. We also discuss the chemokine networks that are putative targets or modulators for augmenting the anti-tumor immune responses in targeted or chemo-/immuno-therapeutic strategies, and how these combinations may be utilized to conquer SCLC.

Rethinking the chemokine cascade in brain metastasis: Preventive and therapeutic implications

Brain metastasis (BrM) is one of the major causes of death in cancer patients and is associated with an estimated 10-40 % of total cancer cases. The survival rate of brain metastatic patients has not improved due to intratumor heterogeneity, the survival adaptations of brain homing metastatic cells, and the lack of understanding of underlying molecular mechanisms that limit the availability of effective therapies. The heterogeneous population of immune cells and tumor-initiating cells or cancer stem cells in the tumor microenvironment (TME) release various factors, such as chemokines that upon binding to their cognate receptors enhance tumor growth at primary sites and help tumor cells metastasize to the brain. Furthermore, brain metastatic sites have unique heterogeneous microenvironment that fuels cancer cells in establishing BrM. This review explores the crosstalk of chemokines with the heterogeneous TME during the progression of BrM and recognizes potential therapeutic approaches. We also discuss and summarize different targeted, immunotherapeutic, chemotherapeutic, and combinatorial strategies (with chemo-/immune- or targeted-therapies) to attenuate chemokines mediated BrM.

Naringenin as a potential inhibitor of human cyclin-dependent kinase 6: Molecular and structural insights into anti-cancer therapeutics

Cancer is one of the major causes of global deaths and needs immediate therapeutic development. So far, several strategies have been undertaken to prevent cancer, including kinase targeting by small-molecule inhibitors. Cyclin dependent kinase 6 (CDK6) plays an essential role in cancer progression and development as its overexpression is associated with tumor development and progression. The present study demonstrated that Naringenin (NAG) binds strongly to CDK6 with a binding affinity of -7.51 kcal/mol. ATPase assay of CDK6 in the presence of NAG shows that it inhibits CDK6 with an IC₅₀ = 3.13 μM. Fluorescence and isothermal titration calorimetry studies demonstrated that NAG binds to CDK6 with the binding constant (K) values of 3.55 × 10⁶ M^-1 and 7.06 ± 2.70 × 10⁶ M^-1, respectively. The cell-based functional studies showed that NAG decreases the cell viability of human cancer cell lines, induces apoptosis, and reduces their colonization ability. Outcomes of the present in silico and in vitro studies highlighted the significance of NAG for the development of anti-cancer leads in terms of CDK6 inhibitors and provided future implications for combinatorial anti-cancer therapies.

Structure-guided design and development of cyclin-dependent kinase 4/6 inhibitors: A review on therapeutic implications

Cyclin-dependent kinase 6 (EC 2.7.11.22) play significant roles in numerous biological processes and triggers cell cycle events. CDK6 controlled the transcriptional regulation. A dysregulated function of CDK6 is linked with the development of progression of multiple tumor types. Thus, it is considered as an effective drug target for cancer therapy. Based on the direct roles of CDK4/6 in tumor development, numerous inhibitors developed as promising anti-cancer agents. CDK4/6 inhibitors regulate the G1 to S transition by preventing Rb phosphorylation and E2F liberation, showing potent anti-cancer activity in several tumors, including HR+/HER2- breast cancer. CDK4/6 inhibitors such as abemaciclib, palbociclib, and ribociclib, control cell cycle, provoke cell senescence, and induces tumor cell disturbance in pre-clinical studies. Here, we discuss the roles of CDK6 in cancer along with the present status of CDK4/6 inhibitors in cancer therapy. We further discussed, how structural features of CDK4/6 could be implicated in the design and development of potential anti-cancer agents. In addition, the therapeutic potential and limitations of available CDK4/6 inhibitors are described in detail. Recent pre-clinical and clinical information for CDK4/6 inhibitors are highlighted. In addition, combination of CDK4/6 inhibitors with other drugs for the therapeutic management of cancer are discussed.

Abstract 1489: MicroRNA-1 targets CXCR4/FOXM1/RRM2 axis regulating small cell lung cancer growth and metastasis

Small cell lung cancer (SCLC) is a high-grade neuroendocrine metastatic lung cancer subtype having a universal relapse and poor prognosis. Limited or extensive-stage SCLC patients have limited therapeutic options due to a lack of potential drug targets. In the quest for novel therapeutic molecules, we performed micro-RNA sequencing from the serum samples and also analyzed bulk RNA-sequencing data from tumors of SCLC patients. We found a consistent downregulation of miR-1 in SCLC. These results were recapitulated in SCLC cell lines and tumor tissues compared to their matched normal. To assess the therapeutic potential of miR-1, we overexpressed miR-1 in SCLC cell lines that translated into decreased cell growth and oncogenic signaling. Mechanistic studies revealed that CXCR4 is a direct target for miR-1 in SCLC. Intracardiac injection of SCLC cell lines in the mouse models showed that overexpression of miR-1 decreases the distant organ metastasis, whereas miR-1 sponging potentiates aggressiveness and metastasis. Furthermore, we identified FOXM1-RRM2 as a unique downstream target of the miR-1/CXCR4 axis involved in the growth and metastasis of SCLC. Our results showed that FOXM1 directly binds to the promoter site of RRM2 and regulates its activity. Overexpression of miR-1 decreases the expression and activity of FOXM1-RRM2 through CXCR4 that reduces cell growth and metastasis. Taken together, our results suggest that miR-1 decreases SCLC metastasis by targeting the CXCR4/FOXM1-RRM2 axis and has a high potential for the development of novel SCLC therapies.

Citation Format: Parvez Khan, Jawed A. Siddiqui, Shailendra Kumar Maurya, Tamara Mirzapoiazova, Ranjana Kanchan, Ramakanth Chirravuri Venkata, Pranita Atri, Wemin Tang, NaveenKumar Perumal, Prakash Kshirsagar, Mahek Fatima, Md Arafat Khan, Sanjib Chaudhary, Asad Ur Rehman, Imayavaramban Lakshmanan, Sidharth Mahapatra, Prakash Kulkarni, Apar Kishor Ganti, Maneesh Jain, David Oupicky, Ravi Salgia, Surinder Kumar Batra, Mohd Wasim Nasser. MicroRNA-1 targets CXCR4/FOXM1/RRM2 axis regulating small cell lung cancer growth and metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1489.

Abstract 3746: Influence of diethylnitrosamine on Mucin 13 expression in hepatocellular carcinoma

Background: Hepatocellular carcinoma (HCC) is regarded as environmental-related cancer due to involvement of chemical carcinogen and viral components in multistage process. Accumulating studies have shown that obesity and non-alcoholic fatty liver disease, which can lead to HCC, have been linked to modern diets that are high in fat and charcoal-grilled processed meat, however, the exact processes through which diet contributes to hepato-carcinogenesis remain unclear. In the present study, we demonstrated that diethylnitrosamine (DEN), a subgroup of the N-nitroso compounds presents in food additive/preservative, tobacco smoke, and pharmaceutical products, upregulates the Mucin 13, transmembrane mucin, via miR-145 suppression accompanied by hepatocarcinogenesis events.

Methodology: Western blotting and qPCR were performed to examine the treatment effects of DEN on Mucin 13 and associated effector proteins in hepatocellular carcinoma cell (HepG2, Hep3B, C3A, and SK-HEP-1) lines. Chemically induced (DEN; 200 mg/kg bw; 2-AAF (150 mg/kg bw) animal model was used to further investigate the Mucin 13 expression. The serum AST, ALT and ALP activity were measured using kits provided by Span diagnostics. Immunohistochemistry was used to stain tumor tissue sections for Mucin 13 expression, and in situ hybridization was performed to detect miR-145 levels. Molecular docking studies were performed using Auto dock 4 package.

Results: Our study demonstrated that DEN treatment facilitates the DNA adducts formation in liver cancer cell lines as compared to vehicle controls. Moreover, DEN treatment upregulates Mucin 13 and associated effector proteins as analyzed by qPCR and Western blotting. Liver section of DEN+2-AAF-administered group showed vacuolization of hepatocytes in the centrizonal area with variation of nuclear size. Clear nuclear atypia in the adenoma was seen. The serum activities of AST, ALP and ALT in diseased animals correlated with the liver cancer progression. Additionally, Mucin 13 was also upregulated by DEN treatment in liver tissues. Intriguingly, nuclear Mucin 13 staining was very less in normal liver tissues, whereas its levels were significantly increased DEN+2-AAF induced HCC. These observations indicate that nuclear localization of Mucin 13 may contribute to the malignant transformation of hepatocytes during carcinogenesis. This revealed significant downregulation of tumor suppressors miR-145 in tumor tissues as compared to normal control. Molecular modelling analysis revealed that DEN interacts with Mucin 13 and forms a stable complex by offering numerous interactions with the residues of Mucin 13.

Conclusions: We propose that DEN modulates Mucin 13 and associated effector proteins in hepatocarcinogenesis.

Citation Format: Shabnam Malik, Mohammed Sikander, Parvez Khan, Murali M. Yallapu, Swatantra Jain, Deepshikha P. Katare, Subhash C. Chauhan, Meena Jaggi. Influence of diethylnitrosamine on Mucin 13 expression in hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3746.

Abstract 2431: A novel role of MUC5AC/CD44v6/c-Met axis in breast cancer brain metastasis

Brain metastasis (BrM) is one of the leading causes of mortality in breast cancer (BC). Although BrM is associated with all BC subtypes, but it is more prevalent in triple-negative and HER2+ BC patients. Recent advancements in the multimodality treatment of primary BC have prolonged patient survival, which has in turn increased the incidence of BrM. Due to the lack of understanding of BC-BrM, there is no reliable biomarker and effective therapeutic strategy. In this regard, using publicly available databases and RNA-Seq analysis, we observed that secretory mucin MUC5AC is significantly upregulated in BC brain metastatic cell lines and tissues compared to their respective control. We validated these observations in brain-seeking BC (BSBC) cell lines and brain metastatic tissues at protein levels. Interestingly, we found that the MUC5AC levels were significantly increased in the serum of CNS metastatic patients relative to healthy donors and BC patients. Our functional studies revealed that silencing of MUC5AC in BSBC cell lines showed a significant decrease in cell adhesion, migration, brain metastatic potential, and increased survival of mice. Exploring the molecular mechanism further revealed that MUC5AC interacts with CD44v6 and c-Met and deletion of MUC5AC demonstrated a decrease in the expression of c-MET and CD44v6. Furthermore, pharmacological targeting of MUC5AC through c-Met inhibitor reduces the expression of CD44v6 and MUC5AC, suggesting that c-Met inhibitors could be used as a novel therapeutics for targeting MUC5AC and thereby attenuating BC brain metastasis. Altogether, our study demonstrates that MUC5AC/CD44v6/c-Met axis could be used as a novel approach to prevent breast cancer brain metastasis.

Citation Format: Shailendra Kumar Maurya, Jawed A. Siddiqui, Shailendra K. Gautama, Ranjana K. Kanchan, Ramesh Pothuraju, Gopalakrishnan Natarajan, Pranita Atri, Ramakanth C. Venkata, Rakesh Bhatia, Parvez Khan, Asad Ur Rehmana, Sanjib Chaudhary, Naveenkumar Perumal, Sidharth Mahapatra, Hitendra S. Chand, Maneesh Jain, Juan A. Santamaria-Barriab, Diana M. Cittelly, Surinder K. Batra, Mohd W. Nasser. A novel role of MUC5AC/CD44v6/c-Met axis in breast cancer brain metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2431.

MEDB-90. Iron Imbalance Can Potentiate Cisplatin Response in Pediatric Medulloblastoma by Regulating Ferroptosis

Medulloblastoma (MB), the most common malignant pediatric brain tumor, is a leading cause of childhood mortality. Of the four primary subgroups, patients with group 3 tumors have the poorest prognosis. Loss of chromosome 17p is a high-risk feature associated with poor outcomes in group 3 tumors. We recently elucidated the tumor suppressive properties of a novel miR, miR-1253, on the terminal end of 17p. In further exploring its anti-neoplastic effects, we discovered that miR-1253 can disrupt iron homeostasis, causing oxidative stress and inducing lipid peroxidation. These concurrent events are capable of triggering an iron-mediated form of cell death called ferroptosis. Notably, our in silico interrogation of ferroptosis regulator genes (FRGs) in group 3 tumors revealed high expression of genes associated with iron transport and glutathione metabolism. These included mitochondrial iron transporters and GPX4, a critical regulator of ferroptosis. Restoration of miR-1253 expression in group 3 cell lines resulted in specific downregulation of ABCB7, an iron-sulfur cluster exporter, and GPX4. Consequently, cytosolic and mitochondrial labile iron pools rose, glutathione levels declined, and mitochondrial oxidative stress and lipid peroxidation were induced. These events were recapitulated by ABCB7 knockdown and potentiated cell death. Treating miR-1253-expressing cancer cells with cisplatin, a group 3 MB chemotherapeutic agent with ferroptotic properties, further elevated oxidative stress, depleted glutathione levels, and augmented lipid peroxidation, with added inhibitory effects on cell viability and colony formation. Treatment with a ferroptosis inhibitor (ferrostatin-1) lead to recovery from the cytotoxic effects of this combination therapy. Our studies highlight a novel mechanism for group 3 MB pathogenesis via ferroptosis regulation and provide a proof-of-concept for exploiting group 3 MB tumor vulnerability to iron imbalance as a novel treatment strategy.

Impact of generic ICD programming on clinical outcomes

Funding Acknowledgements

Type of funding sources: None.

Introduction

Generic ICD programming, where shock-reduction programming is extrapolated from trials of one manufacturer to another, may reduce non-essential ICD therapies beyond that seen in randomised trials. The purpose of this retrospective cohort study was to evaluate the impact of a standardised programming protocol, based on generic programming, across manufacturers. We also evalutated the impact of combining different detection rates and detection times.

Methods

We included all new ICDs in a single centre (2009-2019). In 2013 a standardised programming protocol based on generic programming was introduced. Patients were classified into three groups: pre-guideline (PS), post-guideline and guideline compliant (GC) and post-guideline but not guideline compliant (NGC). The end-points were the first occurrence of any device therapy (ATP or shock), ICD shock, syncope and all-cause mortality. Survival analysis was used to evaluate outcomes. A ’’programming score’’ was composed based on detection rate and time. The relationship between this composite "programming score’’ and study end-points was evaluated in multivariable cox proportional hazards models

Results

1003 patients were included (mean follow-up 1519 +/- 1005 days). In primary prevention patients freedom from ICD therapy (91.5% vs. 73.6%, p<0.001) or shock (94.7% vs 84.8%, p=0.02) were significantly higher in GC compared to PS patients, without significant increase in syncope or mortality. In secondary prevention patients freedom from any ICD therapy or any shock were non-significantly higher in GC compared to PS patients. Among primary prevention patients with the highest ’programming score’ (longest detection time and highest detection rates), there was a 82% reduction in risk of any ICD therapy (p<0.001) and a 70% reduction in risk of ICD shock (p<0.001)

Conclusion

A standardised programming protocol, incorporating generic programming, reduced the burden of ICD therapy without an increase in adverse outcomes.

Liquid biopsies to occult brain metastasis

Brain metastasis (BrM) is a major problem associated with cancer-related mortality, and currently, no specific biomarkers are available in clinical settings for early detection. Liquid biopsy is widely accepted as a non-invasive method for diagnosing cancer and other diseases. We have reviewed the evidence that shows how the molecular alterations are involved in BrM, majorly from breast cancer (BC), lung cancer (LC), and melanoma, with an inception in how they can be employed for biomarker development. We discussed genetic and epigenetic changes that influence cancer cells to breach the blood-brain barrier (BBB) and help to establish metastatic lesions in the uniquely distinct brain microenvironment. Keeping abreast with the recent breakthroughs in the context of various biomolecules detections and identifications, the circulating tumor cells (CTC), cell-free nucleotides, non-coding RNAs, secretory proteins, and metabolites can be pursued in human body fluids such as blood, serum, cerebrospinal fluid (CSF), and urine to obtain potential candidates for biomarker development. The liquid biopsy-based biomarkers can overlay with current imaging techniques to amplify the signal viable for improving the early detection and treatments of occult BrM.

Insights into the Antibacterial Activity of Prolactin-Inducible Protein against the Standard and Environmental MDR Bacterial Strains

Background: Prolactin inducible protein (PIP) is a small secretary glycoprotein present in most biological fluids and contributes to various cellular functions, including cell growth, fertility, antitumor, and antifungal activities. Objectives: The present study evaluated the antibacterial activities of recombinant PIP against multiple broad-spectrum MDR bacterial strains. Methods: The PIP gene was cloned, expressed and purified using affinity chromatography. Disk diffusion, broth microdilution, and growth kinetic assays were used to determine the antibacterial activities of PIP. Results: Disk diffusion assay showed that PIP has a minimum and maximum zone of inhibition against E. coli and P. aeruginosa, respectively, compared to the reference drug ampicillin. Furthermore, growth kinetics studies also suggested that PIP significantly inhibited the growth of E. coli and P. aeruginosa. The minimum inhibitory concentration of PIP was 32 µg/mL for E. coli (443), a standard bacterial strain, and 64 µg/mL for Bacillus sp. (LG1), an environmental multidrug-resistant (MDR) strain. The synergistic studies of PIP with ampicillin showed better efficacies towards selected bacterial strains having MDR properties. Conclusion: Our findings suggest that PIP has a broad range of antibacterial activities with important implications in alleviating MDR problems.

The impact of changing the diagnostic algorithm for TB in Manicaland, Zimbabwe

SETTING

Governmental health facilities performing TB diagnostics in Manicaland, Zimbabwe.

OBJECTIVE

To investigate the effect of making Xpert® MTB/RIF the primary TB diagnostic for all patients presenting with presumptive TB on 1) the number of samples investigated for TB, 2) the proportion testing TB-positive, and 3) the proportion of unsuccessful results over time.

DESIGN

This retrospective study used data from GeneX-pert downloads, laboratory registers and quality assurance reports between 1 January 2017 and 31 December 2018.

RESULTS

The total number of Xpert tests performed in Manicaland increased from 3,967 in the first quarter of 2017 to 7,011 in the last quarter of 2018. Mycobacterium tuberculosis DNA was detected in 4.9-8.6% of the samples investigated using Xpert, with a higher yield in 2017 than in 2018. The overall proportion of unsuccessful Xpert assays due to "no results", errors and invalid results was 6.3%, and highly variable across sites.

CONCLUSION

Roll out of more sensitive TB diagnostics does not necessarily result in an increase of microbiologically confirmed TB diagnosis. While the number of samples tested using Xpert increased, the proportion of TB-positive tests decreased. GeneXpert soft- and hardware infrastructure needs to be strengthened to reduce the rate of unsuccessful assays and therefore, costs and staff time.

Myricetin inhibits breast and lung cancer cells proliferation via inhibiting MARK4

Identifying novel molecules as potential kinase inhibitors are gaining significant attention globally. The present study suggests Myricetin as a potential inhibitor of microtubule-affinity regulating kinase (MARK4), adding another molecule to the existing list of anticancer therapeutics. MARK4 regulates initial cell division steps and is a potent druggable target for various cancers. Structure-based docking with 100 ns molecular dynamics simulation depicted activity of Myricetin in the active site pocket of MARK4 and the formation of a stable complex. The fluorescence-based assay showed excellent affinity of Myricetin to MARK4 guided by static and dynamic quenching. Moreover, the assessment of enthalpy change (∆H) and entropy change (∆S) delineated electrostatic interactions as a dominant force in the MARK4-myricetin interaction. Isothermal titration calorimetric measurements revealed spontaneous binding of Myricetin with MARK4. Further, the kinase assay depicted significant inhibition of MARK4 by Myricetin with IC₅₀  = 3.11 µM. Additionally, cell proliferation studies established that Myricetin significantly inhibited the cancer cells (MCF-7 and A549) proliferation, and inducing apoptosis. This study provides a solid rationale for developing Myricetin as a promising anticancer molecule in the MARK4 mediated malignancies.

BIOL-06. MIR-1253 POTENTIATES CISPLATIN RESPONSE IN PEDIATRIC GROUP 3 MEDULLOBLASTOMA BY REGULATING FERROPTOSIS

Medulloblastoma (MB), the most common malignant pediatric brain tumor and a leading cause of childhood mortality, is stratified into four primary subgroups, i.e. SHH (sonic hedgehog), WNT (wingless), and non-SHH/WNT groups 3 and 4, the latter representing high-risk MB. Haploinsufficiency of 17p13.3, which houses the tumor suppressor gene miR-1253, characterizes high-risk tumors. Despite improvements in targeted therapies, a limited proportion of these patients survive the disease. Capitalizing on the tumor suppressive properties of miRNAs as adjuncts to chemotherapy provides a promising alternative to current therapeutic strategies. In this study, we explored the potentiating effects of miR-1253 on cisplatin cytotoxicity in group 3 MB. First, in silico and in vitro analyses revealed an upregulation of ABCB7, a mitochondrial iron transporter and putative target of miR-1253, in MB cell lines and group 3 MB tumors. Overexpression of miR-1253 resulted in downregulation of ABCB7 and GPX4, a critical ferroptosis regulator, which consequently increased labile mitochondrial iron pool and, in turn, mitochondrial ROS (mtROS). Complementarily, we demonstrated, using CRISPR knockdown of ABCB7, ferroptosis induction with downregulation of GPx4 expression, liberation of free iron, mtROS generation and lipid peroxidation. Cisplatin is reported as an inducer of both apoptosis and ferroptosis-mediated cancer cell death. Therapeutically, the combination of miR-1253 and cisplatin led to an additive effect on cell viability, colony formation, apoptosis, and ROS generation. In turn, treatment with mtROS inhibitor (MnTBAP) and ferroptosis inhibitor (Ferrostatin) lead to partial recovery from the cytotoxic effects of this combination therapy. These studies identify an miR-1253-induced ferroptosis pathway targeting the ABCB7/GPX4/mtROS axis in group 3 MB. They further provide proof-of-concept in using miR-based therapeutics to augment treatment efficacy of current chemotherapeutics in the treatment of high-risk tumors.

MicroRNA-1: Diverse role of a small player in multiple cancers

The process of cancer initiation and development is a dynamic and complex mechanism involving multiple genetic and non-genetic variations. With the development of high throughput techniques like next-generation sequencing, the field of cancer biology extended beyond the protein-coding genes. It brought the functional role of noncoding RNAs into cancer-associated pathways. MicroRNAs (miRNAs) are one such class of noncoding RNAs regulating different cancer development aspects, including progression and metastasis. MicroRNA-1 (miR-1) is a highly conserved miRNA with a functional role in developing skeletal muscle precursor cells and cardiomyocytes and acts as a consistent tumor suppressor gene. In humans, two discrete genes, MIR-1-1 located on 20q13.333 and MIR-1-2 located on 18q11.2 loci encode for a single mature miR-1. Downregulation of miR-1 has been demonstrated in multiple cancers, including lung, breast, liver, prostate, colorectal, pancreatic, medulloblastoma, and gastric cancer. A vast number of studies have shown that miR-1 affects the hallmarks of cancer like proliferation, invasion and metastasis, apoptosis, angiogenesis, chemosensitization, and immune modulation. The potential therapeutic applications of miR-1 in multiple cancer pathways provide a novel platform for developing anticancer therapies. This review focuses on the different antitumorigenic and therapeutic aspects of miR-1, including how it regulates tumor development and associated immunomodulatory functions.

Clinical perspectives on treatment of rifampicin-resistant/multidrug-resistant TB

Rapid diagnostics, newer drugs, repurposed medications, and shorter regimens have radically altered the landscape for treating rifampicin-resistant TB (RR-TB) and multidrug-resistant TB (MDR-TB). There are multiple ongoing clinical trials aiming to build a robust evidence base to guide RR/MDR-TB treatment, and both observational studies and programmatic data have contributed to advancing the treatment field. In December 2019, the WHO issued their second 'Rapid Communication´ related to RR-TB management. This reiterated their prior recommendation that a majority of people with RR/MDR-TB receive all-oral treatment regimens, and now allow for specific shorter duration regimens to be used programmatically as well. Many TB programs need clinical advice as they seek to roll out such regimens in their specific setting. In this Perspective, we highlight our early experiences and lessons learned from working with National TB Programs, adult and pediatric clinicians and civil society, in optimizing treatment of RR/MDR-TB, using shorter, highly-effective, oral regimens for the majority of people with RR/MDR-TB.

Targeting cyclin-dependent kinase 6 by vanillin inhibits proliferation of breast and lung cancer cells: Combined computational and biochemical studies

Cyclin-dependent kinase 6 (CDK6) is a member of serine/threonine kinase family, and its overexpression is associated with cancer development. Thus, it is considered as a potential drug target for anticancer therapies. This study showed the CDK6 inhibitory potential of vanillin using combined experimental and computational methods. Structure-based docking and 200 ns molecular dynamics simulation studies revealed that the binding of vanillin stabilizes the CDK6 structure and provides mechanistic insights into the binding mechanism. Enzyme inhibition and fluorescence-binding studies showed that vanillin inhibits CDK6 with an half maximal inhibitory concentration = 4.99 μM and a binding constant (K) 4.1 × 10⁷ M^-1 . Isothermal titration calorimetry measurements further complemented our observations. Studies on human cancer cell lines (MCF-7 and A549) showed that vanillin decreases cell viability and colonization properties. The protein expression studies have further revealed that vanillin reduces the CDK6 expression and induces apoptosis in the cancer cells. In conclusion, our study presents the CDK6-mediated therapeutic implications of vanillin for anticancer therapies.

RNA-based therapies: A cog in the wheel of lung cancer defense

Lung cancer (LC) is a heterogeneous disease consisting mainly of two subtypes, non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC), and remains the leading cause of death worldwide. Despite recent advances in therapies, the overall 5-year survival rate of LC remains less than 20%. The efficacy of current therapeutic approaches is compromised by inherent or acquired drug-resistance and severe off-target effects. Therefore, the identification and development of innovative and effective therapeutic approaches are critically desired for LC. The development of RNA-mediated gene inhibition technologies was a turning point in the field of RNA biology. The critical regulatory role of different RNAs in multiple cancer pathways makes them a rich source of targets and innovative tools for developing anticancer therapies. The identification of antisense sequences, short interfering RNAs (siRNAs), microRNAs (miRNAs or miRs), anti-miRs, and mRNA-based platforms holds great promise in preclinical and early clinical evaluation against LC. In the last decade, RNA-based therapies have substantially expanded and tested in clinical trials for multiple malignancies, including LC. This article describes the current understanding of various aspects of RNA-based therapeutics, including modern platforms, modifications, and combinations with chemo-/immunotherapies that have translational potential for LC therapies.

A Fluorescence Resonance Energy Transfer-Based Analytical Tool for Nitrate Quantification in Living Cells

Nitrate (NO₃ ^-) is a critical source of nitrogen (N) available to microorganisms and plants. Nitrate sensing activates signaling pathways in the plant system that impinges upon, developmental, molecular, metabolic, and physiological responses locally, and globally. To sustain, the high crop productivity and high nutritional value along with the sustainable environment, the study of rate-controlling steps of a metabolic network of N assimilation through fluxomics becomes an attractive strategy. To monitor the flux of nitrate, we developed a non-invasive genetically encoded fluorescence resonance energy transfer (FRET)-based tool named "FLIP-NT" that monitors the real-time uptake of nitrate in the living cells. The developed nanosensor is suitable for real-time monitoring of nitrate flux in living cells at subcellular compartments with high spatio-temporal resolution. The developed FLIP-NT nanosensor was not affected by the pH change and have specificity for nitrate with an affinity constant (K _d) of ∼5 μM. A series of affinity mutants have also been generated to expand the physiological detection range of the sensor protein with varying K _d values. It has been found that this sensor successfully detects the dynamics of nitrate fluctuations in bacteria and yeast, without the disruption of cellular organization. This FLIP-NT nanosensor could be a very important tool that will help us to advance the understanding of nitrate signaling.

Epigenetic landscape of small cell lung cancer: small image of a giant recalcitrant disease

Small cell lung cancer (SCLC) is a particular subtype of lung cancer with high mortality. Recent advances in understanding SCLC genomics and breakthroughs of immunotherapy have substantially expanded existing knowledge and treatment modalities. However, challenges associated with SCLC remain enigmatic and elusive. Most of the conventional drug discovery approaches targeting altered signaling pathways in SCLC end up in the 'grave-yard of drug discovery', which mandates exploring novel approaches beyond inhibiting cell signaling pathways. Epigenetic modifications have long been documented as the key contributors to the tumorigenesis of almost all types of cancer, including SCLC. The last decade witnessed an exponential increase in our understanding of epigenetic modifications for SCLC. The present review highlights the central role of epigenetic regulations in acquiring neoplastic phenotype, metastasis, aggressiveness, resistance to chemotherapy, and immunotherapeutic approaches of SCLC. Different types of epigenetic modifications (DNA/histone methylation or acetylation) that can serve as predictive biomarkers for prognostication, treatment stratification, neuroendocrine lineage determination, and development of potential SCLC therapies are also discussed. We also review the utility of epigenetic targets/epidrugs in combination with first-line chemotherapy and immunotherapy that are currently under investigation in preclinical and clinical studies. Altogether, the information presents the inclusive landscape of SCLC epigenetics and epidrugs that will help to improve SCLC outcomes.

Inhibiting CDK6 Activity by Quercetin Is an Attractive Strategy for Cancer Therapy

Cyclin-dependent kinase 6 (CDK6) is a potential drug target that plays an important role in the progression of different types of cancers. We performed in silico and in vitro screening of different natural compounds and found that quercetin has a high binding affinity for the CDK6 and inhibits its activity with an IC50 = 5.89 μM. Molecular docking and a 200 ns whole atom simulation of the CDK6-quercetin complex provide insights into the binding mechanism and stability of the complex. Binding parameters ascertained by fluorescence and isothermal titration calorimetry studies revealed a binding constant in the range of 107 M-1 of quercetin to the CDK6. Thermodynamic parameters associated with the formation of the CDK6-quercetin complex suggested an electrostatic interaction-driven process. The cell-based protein expression studies in the breast (MCF-7) and lung (A549) cancer cells revealed that the treatment of quercetin decreases the expression of CDK6. Quercetin also decreases the viability and colony formation potential of selected cancer cells. Moreover, quercetin induces apoptosis, by decreasing the production of reactive oxygen species and CDK6 expression. Both in silico and in vitro studies highlight the significance of quercetin for the development of anticancer leads in terms of CDK6 inhibitors.

Setting up pharmacovigilance based on available endTB Project data for bedaquiline

SETTING: Active pharmacovigilance (PV) is recommended for TB programmes, notably for multidrug-resistant TB (MDR-TB) patients treated with new drugs. Launched with the support of UNITAID in April 2015, endTB (Expand New Drug markets for TB) facilitated treatment with bedaquiline (BDQ) and/or delamanid of >2600 patients in 17 countries, and contributed to the creation of a central PV unit (PVU).OBJECTIVE: To explain the endTB PVU process by describing the serious adverse events (SAEs) experienced by patients who received BDQ-containing regimens.DESIGN: The overall PV strategy was in line with the ‘advanced´ WHO active TB drug safety monitoring and management (aDSM) system. All adverse events (AEs) of clinical significance were followed up; the PVU focused on signal detection from SAEs.RESULTS and CONCLUSION: Between 1 April 2015 and 31 March 2019, the PVU received and assessed 626 SAEs experienced by 417 BDQ patients. A board of MDR-TB/PV experts reviewed unexpected and possibly drug-related SAEs to detect safety signals. The experts communicated on clusters of risks factors, notably polypharmacy and off-label drug use, encouraging a patient-centred approach of care. Organising advanced PV in routine care is possible but demanding. It is reasonable to expect local/national programmes to focus on clinical management, and to limit reporting to aDSM systems to key data, such as the SAEs.

Introducing new and repurposed TB drugs: the endTB experience

In 2015, the initiative Expand New Drug Markets for TB (endTB) began, with the objective of reducing barriers to access to the new and repurposed TB drugs. Here we describe the major implementation challenges encountered in 17 endTB countries. We provide insights on how national TB programmes and other stakeholders can scale-up the programmatic use of new and repurposed TB drugs, while building scientific evidence about their safety and efficacy. For any new drug or diagnostic, multiple market barriers can slow the pace of scale-up. During 2015-2019, endTB was successful in increasing the number of patients receiving new and repurposed TB drugs in 17 countries. The endTB experience has many lessons, which are relevant to country level introduction of new TB drugs, as well as non-TB drugs and diagnostics. For example: the importation of TB drugs is possible even in the absence of registration; emphasis on good clinical monitoring is more important than pharmacovigilance reporting; national guidelines and expert committees can both facilitate and hinder innovative practice; clinicians use new and repurposed TB drugs when they are available; data collection to generate scientific evidence requires financial and human resources; pilot projects can drive national scale-up.

Design and Development of Small-Molecule Arylaldoxime/5-Nitroimidazole Hybrids as Potent Inhibitors of MARK4: A Promising Approach for Target-Based Cancer Therapy

Microtubule affinity-regulating kinase 4 (MARK4), a member of the serine/threonine kinase family, is an emerging therapeutic target in anticancer drug discovery paradigm due to its involvement in regulation of microtubule dynamics, cell cycle regulation, and cancer progression. Therefore, to identify the novel chemical architecture for the design and development of novel MARK4 inhibitors with concomitant radical scavenging property, a series of small-molecule arylaldoxime/5-nitroimidazole conjugates were designed and synthesized via multistep chemical reactions following the pharmacophoric hybridization approach. Compound 4h was identified as a promising MARK4 inhibitor with high selectivity toward MARK4 inhibition as compared to the panel of screened 30 kinases pertaining to the serine/threonine family, which was validated by molecular docking and fluorescence binding studies. The comprehensive cell-based examination divulged the promising apoptotic, antiproliferative, and antioxidant potential for the chemotype 4h. The compound 4h was endowed with the K _a value of 3.6 × 10³ M^-1 for human serum albumin, which reflects its remarkable transportation and delivery properties to the target site via blood. The present study impedes that in the future, such compounds may stand as optimized pharmacological lead candidates in drug discovery for targeting cancer via MARK4 inhibition with a remarkable anticancer profile.

Unravelling the unfolding pathway of human Fas-activated serine/threonine kinase induced by urea

Fas-activated serine/threonine kinase (FASTK) is a mitochondria-associated nuclear protein that inhibits Fas- and UV-induced apoptosis. This protein is generally activated during Fas-mediated apoptosis by phosphorylating a nuclear RNA-binding protein T-cell intracellular antigen-1 and thus considered as a modulator of apoptosis. In the present study, we have examined the equilibrium unfolding and conformational stability of the kinase domain of FASTK (FASTK_353-444). The kinase domain of FASTK_353-444 was cloned, expressed, and purified. The folding ↔ unfolding transitions of urea-induced denaturation was monitored with the help of circular dichroism, intrinsic fluorescence, and UV absorption spectroscopies. Analysis of transition curves obtained from different probes revealed a coincidence of denaturation curves, suggesting that folding/unfolding of FASTK follows a two-state process with the midpoint (C_m) value at 3.50 ± 0.1 M. Urea-induced denaturation curves were further analyzed to estimate change in the Gibbs free energy in the absence of urea (ΔG_D⁰) associated with the equilibrium of denaturation. To get atomistic insights into the urea-induced denaturation of FASTK, we performed an all-atom molecular dynamics simulation for 100 ns. A close agreement was noticed between experimental and computational studies. This study will help to understand the unfolding mechanism and structural stability of the kinase domain of FASTK.Communicated by Ramaswamy H. Sarma.

Rosmarinic Acid Exhibits Anticancer Effects via MARK4 Inhibition

Microtubule affinity regulating kinase (MARK4) is a potential drug target for different types of cancer as it controls the early step of cell division. In this study, we have screened a series of natural compounds and finally identified rosmarinic acid (RA) as a potential inhibitor of MARK4. Molecular docking and 500 ns all-atom simulation studies suggested that RA binds to the active site pocket of MARK4, forming enough number of non-covalent interactions with critical residues and MARK4-RA complex is stable throughout the simulation trajectory. RA shows an excellent binding affinity to the MARK4 with a binding constant (K) of 107 M-1. Furthermore, RA significantly inhibits MARK4 activity (IC50 = 6.204 µM). The evaluation of enthalpy change (∆H) and entropy change (∆S) suggested that the MARK4-RA complex formation is driven by hydrogen bonding and thus complexation process is seemingly specific. The consequence of MARK4 inhibition by RA was further evaluated by cell-based tau-phosphorylation studies, which suggested that RA inhibited the phosphorylation of tau. The treatment of cancer cells with RA significantly controls cell growth and subsequently induces apoptosis. Our study provides a rationale for the therapeutic evaluation of RA and RA-based inhibitors in MARK4 associated cancers and other diseases.

Ellagic Acid Controls Cell Proliferation and Induces Apoptosis in Breast Cancer Cells via Inhibition of Cyclin-Dependent Kinase 6

Cyclin-Dependent Kinase 6 (CDK6) plays an important role in cancer progression, and thus, it is considered as an attractive drug target in anticancer therapeutics. This study presents an evaluation of dietary phytochemicals, capsaicin, tocopherol, rosmarinic acid, ursolic acid, ellagic acid (EA), limonene, caffeic acid, and ferulic acid for their potential to inhibit the activity of CDK6. Molecular docking and fluorescence binding studies revealed appreciable binding affinities of these compounds to the CDK6. Among them, EA shows the highest binding affinity for CDK6, and thus a molecular dynamics simulation study of 200 ns was performed to get deeper insights into the binding mechanism and stability of the CDK6-EA complex. Fluorescence binding studies revealed that EA binds to the CDK6 with a binding constant of K = 107 M-1 and subsequently inhibits its enzyme activity with an IC50 value of 3.053 µM. Analysis of thermodynamic parameters of CDK6-EA complex formation suggested a hydrophobic interaction driven process. The treatment of EA decreases the colonization of cancer cells and induces apoptosis. Moreover, the expression of CDK6 has been downregulated in EA-treated human breast cancer cell lines. In conclusion, this study establishes EA as a potent CDK6 inhibitor that can be further evaluated in CDK6 directed anticancer therapies.

Synthesis and SAR studies of novel 1,2,4-oxadiazole-sulfonamide based compounds as potential anticancer agents for colorectal cancer therapy

A diverse series of 1,2,4-oxadiazoles based substituted compounds were designed, synthesized and evaluated as anticancer agents targeting carbonic anhydrase IX (CAIX). Initial structure-activity analysis suggested that the thiazole/thiophene-sulfonamide conjugates of 1,2,4-oxadiazoles exhibited potent anticancer activities with low μM potencies. Compound OX12 exhibited antiproliferative activity (IC₅₀ = 11.1 µM) along with appreciable inhibition potential for tumor-associated CAIX (IC₅₀ = 4.23 µM) isoform. Therefore, OX12 was structurally optimized and its SAR oriented derivatives (OX17-27) were synthesized and evaluated. This iteration resulted in compound OX27 with an almost two-fold increase in antiproliferative effect (IC₅₀ = 6.0 µM) comparable to the clinical drug doxorubicin and significantly higher potency against CAIX (IC₅₀ = 0.74 µM). Additionally, OX27 treatment decreases the expression of CAIX, induces apoptosis and ROS production, inhibited colony formation and migration of colon cancer cells. Our studies provide preclinical rational for the further optimization of identified OX27 as a suitable lead for the possible treatment of CRC.